Process and apparatus for opening folded printed products

Abstract

Folded printed products are transported while held in suspended position at their fold and supported in their end region remote from the fold. The end section of the first product part, projecting with respect to the second product part, is seized and temporarily held by a gripper which is driven in a circulating manner. A stabbing element, driven at a different speed with respect to the gripper, then stabs into the printed product and lifts the second product part off the held first product part while the gripper moves away from the stabbing element. With the printed product open, the gripper releases the first product part.

I claim: 
     
       1. An apparatus for opening folded printed products having a first product part and a second product part joined at a fold, each of said product parts having a free end edge opposite the fold, the apparatus comprising: a conveying device including a plurality of transport clips, the transport clips being driven in a conveying direction and each clip adapted to hold a printed product at the fold and extending transversely to the conveying direction;   a supporting element arranged underneath the conveying device for supporting the printed products in the region of their free ends as the products are conveyed; and   an opening unit adjacent the supporting element including a plurality of grippers driven in a circulating manner and each gripper adapted to seize the free edge of one of said product parts in each product;   said opening unit also including a stabbing element moveable relative to the grippers and effective to move between the product parts in each product and at least partially move the other part away from the one part whereby the printed product is opened.   
     
     
       2. The apparatus of claim 1 wherein: said opening unit also includes a product holding-open element;   said holding-open element having a spiral configuration and adapted to rotate about a longitudinal axis extending generally in the conveying direction;   rotation of said spiral element being effective to hold open each opened printed product after its release by a gripper and before its release by a clip.   
     
     
       3. A process for opening folded printed products wherein the fold joins a first product part to a second product part, the method comprising the steps of: holding suspended the printed products at their fold, the fold running transversely to a conveying direction and supported at their end region lying opposite the fold;   conveying the printed products in the conveying direction;   seizing the first product part and temporarily holding it at its end edge, lying opposite the fold, with a gripper;   driving the gripper approximately in the direction of movement of the end edge;   moving the other, second product part away from the held first product part;   stabbing the printed product between the held first product part and the second product part with a stabbing element, movable relative to the gripper;   moving the stabbing element and gripper away from each other such that while the stabbing element is moving away from the gripper, the second product part is at least partially lifted off of the first product part, whereby the printed product is opened.   
     
     
       4. The process as claimed in claim 3 wherein the printed products are folded off-center wherein: the holding step comprises holding the off-center printed product in an approximately vertical suspended position and supporting the printed products in their end region such that, in the end region, the end section of the first product part projects beyond the second product part and is upper-lying; and   wherein the first product part is seized and held at the end section by the gripper and the printed products are stabbed from underneath the end section by the stabbing element.   
     
     
       5. The process as claimed in claim 3 comprising: arranging a spiral-like holding-open element such that its longitudinal axis runs in the conveying direction;   rotatably driving the spiral-like holding-open element about its longitudinal axis; and   engaging the spiral-like holding-open element between the product parts, lifted at least partially off each other, to hold the printed products open after release of the first product part by the grippers.   
     
     
       6. An apparatus for opening folded printed products having a first product part and a second product part, the apparatus comprising: a conveying device including transport clips, the transport clips being driven in a conveying direction and hold the printed products suspended at their fold, running transversely to the conveying direction and joining two product parts to each other;   a supporting element, arranged underneath the conveying device, the supporting element supporting the printed products at their end region lying opposite the fold; and   an opening unit, arranged underneath the conveying device, the opening unit including:   1) a plurality of controllable grippers, driven in a circulating manner along a closed circulating path which runs by the supporting element, the grippers seizing the one, first product part at its end edge, lying opposite the fold;   2) an actively holding region subsequent to where the printed products are seized, including means for actuating the grippers to temporary hold the first product part, and means for moving the other, second product part away from the held first product part; and   3) a stabbing element, which is movable relative to the grippers, the stabbing element stabbing into the printed products between the held first product part and the second product part within the actively holding region of the circulating path of the grippers wherein, during the moving away of gripper and stabbing element from each other, the stabbing element lifts the second product part at least partially off of the first product part, whereby the printed product is opened.   
     
     
       7. The apparatus as claimed in claim 6 wherein: the grippers are arranged on a carrying member, which is driven in a rotating manner;   the opening unit includes a plurality of stabbing elements, driven in a circulating manner along a closed path of movement, a section of the path of movement running by the actively holding region of the circulating path of the grippers; and   the speed of the stabbing elements in the section is variable relative to the circulating speed of the grippers.   
     
     
       8. The apparatus as claimed in claim 6 wherein: the grippers are arranged on a carrying member, which is driven in a rotating manner;   the opening unit includes a plurality of stabbing elements, driven in a circulating manner along a closed path of movement, a section of the path of movement running by the actively holding region of the circulating path of the grippers; and   the speed of the stabbing elements in the section is different relative to the circulating speed of the grippers.   
     
     
       9. The apparatus as claimed in claim 8 wherein between respectively neighboring grippers, there is between the circulating path of the grippers and the carrying member a free space, into which the second product part can engage during opening of the printed products. 
     
     
       10. The apparatus as claimed in claim 9 wherein the carrying member comprises a star-like member including radially projecting carrying arms with radial end regions, and wherein the grippers are disposed on the radial end regions. 
     
     
       11. The apparatus as claimed in claim 10 wherein each of the grippers comprises a fixedly arranged gripper jaw and a movable gripper tongue which interact with each other and wherein the fixedly arranged gripper jaw is arranged on the radially outer end of the carrying arm. 
     
     
       12. The apparatus as claimed in claim 11 comprising a plurality of pivotally mounted substantially U-shaped control levers, each of the control levers disposed on one of the carrying arms and bearing a gripper tongue, which interacts with a gripper jaw, the gripper jaw being fixedly arranged on a neighboring carrying arm. 
     
     
       13. The apparatus as claimed in claim 12 wherein the control levers are prestressed in the direction counter to the closed position of the grippers and comprising a link to swivel the control levers in the opposite direction in order to open the grippers. 
     
     
       14. The apparatus as claimed in claim 8 wherein each gripper is assigned a stabbing element, which is mounted on the carrying member and the path of movement of which, seen in the radial direction, forms a tangent to the circulating path, for stabbing in the actively holding region of the circulating path of the grippers. 
     
     
       15. The apparatus as claimed in claim 8 wherein each gripper is assigned a stabbing element, which is mounted on the carrying member and the path of movement of which, seen in the radial direction, intersects the circulating path, for stabbing in the actively holding region of the circulating path of the grippers. 
     
     
       16. The apparatus as claimed in claim 8 comprising a rotatingly driven stabbing wheel, with stabbing elements arranged as projecting radially, the circumferential speed of the stabbing wheel being different from the speed of the grippers. 
     
     
       17. The apparatus as claimed in claim 8 comprising: a pivotally mounted bearing element having radially projecting bearing arms, the stabbing elements being arranged on the radially projecting bearing arms; and   controlled clamping levers arranged on the bearing arms, the controlled clamping levers interacting with the stabbing elements, in order firmly to clamp the second product part temporarily after the stabbing into a printed product.   
     
     
       18. The apparatus as claimed in claim 6 comprising a vacuum source and wherein the gripper jaws and gripper tongues have openings, for connection to the vacuum source, in order to hold the two product parts during opening of the grippers and lift them off each other at the border lying opposite the fold, and wherein the stabbing elements stab between the product parts thereby lifted off each other. 
     
     
       19. The apparatus as claimed in claim 6 wherein: the printed products are folded off-center such that they have on their first product part an end section projecting beyond the second product part;   the transport clips transport the off-center folded printed products in an approximately vertical suspended position and with the first product part trailing with respect to the second product part;   the supporting element includes a fixed supporting member, in order to support the printed products with, seen in the conveying direction, rearwardly bent end region and upper-lying end section;   the mouths of the grippers are, seen in circulating direction, directed forward; and   the stabbing elements move at a greater speed than the grippers.   
     
     
       20. The apparatus as claimed in claim 6 wherein: the printed products are folded off-center such that they have on their first product part an end section projecting beyond the second product part;   the transport clips transport the off-center folded printed products in an approximately vertical suspended position and with the first product part leading with respect to the second product part;   the supporting element includes a supporting belt, the supporting belt driven in a circulating manner at a greater speed relative to the transport clips, in order to support the printed products with, seen in the conveying direction, forwardly bent end region and upper-lying end section;   the mouths of the grippers are, seen in circulating direction directed rearward; and   the stabbing elements move at lower speed than the grippers.   
     
     
       21. The apparatus as claimed in claim 6 wherein the opening unit comprises a spiral-like holding-open element, the spiral-like holding-open element driven rotatingly about its longitudinal axis, running in the conveying direction, and the spiral-like holding-open element engaging with its rear end, seen in the conveying direction, in each case between the product parts which have been lifted off of each other, in order to hold the opened printed products open after release of the first product part by the grippers during further transport. 
     
     
       22. The apparatus as claimed in claim 21 comprising a processing drum following the opening unit, the processing drum having saddle-shaped rests, onto which the opened printed products are deposited astride by opening of the transport clips, the rests engaging from below between the turns of the holding-open element and the product parts, lifted off each other. 
     
     
       23. The apparatus as claimed in claim 21 wherein the pitch of the turns of the holding-open element increases from its rear end toward its front end. 
     
     
       24. The apparatus as claimed in claim 21 wherein the holding-open element is fastened displaceably in the direction of its longitudinal axis on an input shaft. 
     
     
       25. The apparatus as claimed in claim 21 comprising a vacuum source and wherein the holding-open element includes a feed, connected to the vacuum source, in order to suck the product parts to the feed. 
     
     
       26. The apparatus as claimed in claim 21 comprising a pressure source and wherein the holding-open element includes a feed, connected to the pressure source, in order to direct compressed air against the product parts.